Summary
We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
During the manufacturing process of the Poppet Covers of the Pressurization Safety Valves, burrs that could damage the Valve Diaphragms were not removed. The damage may eventually cause faulty operation of the relief valves resulting in an unsafe condition when combined with additional failures. The serial numbers of the defective valves and the affected aircraft were identified.
The unsafe condition is damage and subsequent failure of the safety relief valves, which could result in rapid decompression of the airplane. The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI.